Many arrangements of groove segments on the braking surfaces of the brake discs of vehicles are known. One such is that disclosed for example in U.S. Pat. No. 7,097,006, which itself references a large number of groove arrangements.
Groove segments are aids, in heat dissipation, stress relief and vibration reduction, and need to be tailored to the particular characteristics and construction of the disc to which they are applied.
A difficulty has been to derive a pattern of groove segments which meets these requirements but is also effective in a disc rotating in either clockwise or anti-clockwise directions so that the disc may be used on either side of a vehicle and provide balanced and equal braking performances regardless of the direction of rotation.
Furthermore, the configuration of the actual machined slot has implications for both the performance of the brake pads applied to the disc surfaces and the integrity of the disc itself. Thus some known slot configurations at least, have either a tendency to tearing of the rotor surfaces or to cause hairline crack development at the brake band peripheries, or both.
Another problem with conventional brake discs is that there is no way a motorist can monitor the braking performance of the braking assembly of the vehicle. Braking efficiency and problems of incompatibility between brake pads and the brake bands of the disc can be indicated by the temperature of the discs after heavy braking, but this temperature can only be ascertained by use of sophisticated thermal monitoring equipment.
It is an object of the present invention to address or at least ameliorate some of the above disadvantages.
Notes
The term “comprising” (and grammatical variations thereof) is used in this specification in the inclusive sense of “having” or “including”, and not in the exclusive sense of “consisting only of”.
The above discussion of the prior art in the Background of the invention, is not an admission that any information discussed therein is citable prior art or part of the common general knowledge of persons skilled in the art in any country.
In this specification:                “Arcuate groove” means a groove following an arc of a circle or other geometrically defined curve.        “Clockwise” and “anti-clockwise” refer to rotational directions about the centre of a brake disc as viewed from the outward side.        